Request data flow, or data flow, refers to control of flow of requests in a network environment. For example, in a transaction system a request may be a transaction request. Flow control may include management of request distribution and/or proper handling of a request, such as whether to refuse or queue a request. Flow control is critical for Internet service provider (ISP) when responding to users' in online activities, such as online browsing, Express Payment, etc. For example, WeChat is a social communication platform allowing registered user to conduct online instant messaging, writing blogs, and make online payment etc. A WeChat user may use WeChat to browse Internet content (e.g., blogs, webpages, etc.). When the user binds his/her WeChat account with a bank account, the user may also use WeChat to conduct a Express Payment without having to login the bank account. Flow control is critical to these services. This is because some ISPs, such as WeChat with Express Payment, have massive user bases. Thus the number of requests the ISPs received every day is massive. Also, users of the social communication platform, such as WeChat, can be active at any time during a day and can stay active for a long period of time. Thus the ISP may receive requests from users at any time of the day and any day during a week. Further, often times the ISP relies on unstable third party service providers to process its service to users. For example, Express Payment may rely on unstable service from banks to process transaction requests from the massive users of WeChat. It is challenging to provide a stable service to users based on the unstable service of the third party service provider.
Generally, traditional flow control is implemented using empirical threshold of static configuration. Specifically, empirical threshold of static configuration is configured to limit data flow when the data flow of a computer (e.g., a server) exceeds the empirical threshold. However, the method is depended on empirical threshold of static configuration. For an Internet service provider adopting distributed flow control, the static configuration needs manual maintenance and it is vulnerable to human error. Besides, the simplex flow control mode, based on empirical thresholds, may lead to load unbalanced and insufficient use of resources.